Magnetism Prezi

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Transcript of Magnetism Prezi

Made By Background Information Classification of Magnets Permanent Magnets Electric Field VS Magnetic Field The Prospects and Implications of Magnetism Satya Bodduluri, Utkash Dubey, Keshav Varma C Period Group 2 Magnetic Field Magnetic Moment Magnetism Three main types Temporary Magnets Electromagnets Superconductors Magnets that create their own persistent magnetic field Examples:refrigerator magnetsneodymium (earth) magnets Metals that are readily magnetized but retain a very small field after the external magnetic field is removed Examples:paperclipsrefrigerator doorsiron Magnet whose magnetic field is created by the flow of artificial electrical current Materials with zero resistance when brought to a certain temperature (Chubukov, Efremov, Eremin, 2008). Examples:speakersmotorsdoorbell Examples:MRIparticle acceleratorsmagnetic levitation trains (Maglev) Diamagnetism Ferromagnetism Paramagnetism ("Types of Magnetism", n.d.) ("Types of Magnetism", n.d.) ("Types of Magnetism", n.d.) Ferrofluid (video) first magnetism observed by humans, most prominent in naturestrongest type and only one to be commonly considered magneticall permanent magnets are either ferromagnetic or ferrimagnetic (different magnetic moments) mixture of magnetic particles in a liquidthe liquid contains surfactantsurfactant keeps particles from clumpingmagnetic particles in the solution are attracted to the magnet, but the surfactant will keep the magnetic particles from clumping completely similar to diamagnetismalso occurs as a result of disrupted orbital velocitiesmagnetism triggered by external magnetic fieldattracted to external magnetic fieldelements with unpaired valence elctrons Demo - Copper Pipe Faraday’s law: change in magnetic environment of a coil of wire causes a voltage to be induced in the coilas the magnet falls, it induces a current in the pipe which then creates a weak magnetic field, slowing the fall of the magnet (Diamagnetism, n.d.) How magnets are made Challenge rare earth metals are extremely expensive to process and are in short supply (Biello, 2010)prices have increased 300-700% in the last year (Galluci, 2011)if our sources of rare earth metals are exhausted, effective replacements will be necessary to perform their taskscurrently, nothing performs to the extent of rare earth magnets without any extra complications Advantages/Disadvantages Current applications Because of their invisible forces, magnets have many different practical applications including:Credit cardsMRIMotorsGeneratorsComputers movement of electric charges (electrons) (Nave, n.d.)most metals: negligible properties, ambiguous magnetism vectors multiple electrons with the same spin --> magnetic moment increases (Nave, n.d.) Ferromagnets (Magnetic Field, n.d.) Advantages Disadvantages materials' response to an externally applied magnetic fieldall materials are influenced by magnetic fields (Wilson, 2007)substances with minimal response considered non-magnetic (i.e. aluminum, copper, plastic) (Wilson, 2007) no energy required to maintain magnetic field strong ferromagnets rely on rare-earth materials that are expensive to mine and process ---------- electrons without an opposite spinning partner create magnetic moment (“Ferromagnetic Materials”, 2008)ferromagnets have multiple unpaired electrons attraction-repulsion vector; magnitude and direction, measured in teslascombined strength of vectors give overall magnetic moment (“Ferromagnetic Materials”, 2008) (Inside an Atom, n.d.) Disadvantages ---------- Advantages require cryogenic (below -150 C) temperatures Superconductors very strong, no energy wasted as heat Advantages Requires lots of energy, much of it released as heat controllable state based on energy put in Disadvantages Electromagnets ---------- Cutting Edge Research New uses for magnetic forces are being developed: